Page ID on change page event

[admin]

New firmware has showplan event which can be used to get new plan id when it changes.
Use this custom JS, it attaches to all elements with back class and replaces click handler with "back" action.

Code:

$(function() {
  var curr_id = currentPlanId, prev_id;

  $('body').on('showplan', function(event, new_id) {
    prev_id = curr_id;
    curr_id = new_id;
  });
  
  $('.back').off('vclick').on('vclick', function() {
    showPlan(prev_id);
  });
});